Customized Thin Film Optical Element Fabrication System and Method

ABSTRACT

A system comprising (i) thin film optical element comprising substrate and thin film stack (≥2 film layers; uniform thickness—variation of less than ±5% in any 10 mm2 stack) deposited on substrate&#39;s first side; (ii) holder comprising at least one opening; wherein holder has inner side and outer side having beveled edge extending into lip having flat side and beveled edge side; wherein beveled edge/beveled edge side of lip form angle &lt;45° with flat side of lip/first side; wherein flat side of lip and holder inner side define socket receiving substrate; wherein opening exposes first side to deposition plume; wherein first side contacts flat side of lip, thereby allowing film stack deposition on first side; wherein beveled edge side/beveled edge provide film uniformity, and (iii) deposition source providing plume traveling towards first side perpendicular to flat side of lip/first deposition side; and wherein beveled edge side faces plume.

BACKGROUND

This disclosure relates to methods of making thin film optical elements.More specifically, it relates to methods of fabricating customized thinfilm optical elements that do not require a size adjustment prior toemploying in an opticoanalytical device.

Optical computing devices, also commonly referred to as opticoanalyticaldevices, can be used to analyze and monitor a sample substance in realtime. Optical computing devices may employ optical processing elements,such as integrated computational elements (ICEs), which may also bereferred to as ICE cores. An ICE can be an optical substrate withmultiple stacked dielectric layers (e.g., from about 2 to about 50layers), each layer having a different complex refractive index from itsadjacent layers. The specific number of layers, N, the opticalproperties (e.g. real and imaginary components of complex indices ofrefraction) of the layers, the optical properties of the substrate, andthe physical thickness of each of the layers that compose the ICE can beselected so that the light processed by the ICE is related to one ormore characteristics of the sample. Because ICEs extract informationfrom the light modified by a sample passively, ICEs can be incorporatedin low cost and rugged optical analysis tools. Hence, ICE-based downholeoptical analysis tools can provide a relatively low cost, rugged andaccurate system for monitoring quality of wellbore fluids, for instance.

However, errors in fabrication of the constituent layers of an ICE cannegatively impact the performance of the ICE. In most cases, fairlysmall deviations (e.g., <0.1%) from point by point design values ofcomplex indices of refraction, and/or thicknesses of the formed layersof the ICE can substantially impact the ICE's performance, in some casesto such an extent, that the ICE becomes operationally useless.Ultra-high accuracies required by ICE designs challenge the state of theart in thin film deposition techniques.

Generally, thin film fabrication techniques for optics are applied tobulk systems, wherein a large number of identical optical elements arefabricated on the same large substrate and are subsequently sized (e.g.,cored) into smaller optical elements of desirable shapes. The elementsare usually fabricated on large substrates in thin film depositionsystems, which may either employ physical vapor deposition techniques orchemical vapor deposition techniques. Unique challenges occur whentrying to fabricate a small number of customized thin film opticalelements. For physical vapor deposition methods (e.g., ion-assistedE-beam deposition), challenges include the difficulty associated withfixating the substrates with respect to the deposition plume. Securingthe substrates typically involves resting the substrate on a beveled lipmachined out of a platter and held in place by gravity. Other options tosecure the substrates (including vacuum, magnetic, electrostatic, andmechanical/compression) are not viable due to the pre-requisites of theenvironment within the deposition chamber. These challenges areexacerbated when trying to fabricate small elements on substrates ofless than about 0.5 inches, wherein quality control becomes difficultand must be applied to each element. Thus, an ongoing need exists forfabricating multi-layer thin optical elements that do not require a sizeadjustment subsequent to depositing the multi-layers on a substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and theadvantages thereof, reference is now made to the following briefdescription, taken in connection with the accompanying drawings anddetailed description, wherein like reference numerals represent likeparts.

FIG. 1 displays a schematic of a substrate holder.

FIG. 2 displays a schematic of a system for making a thin film opticalelement.

FIG. 3 displays a schematic of another system for making a thin filmoptical element.

FIG. 4 displays a schematic of yet another system for making a thin filmoptical element.

FIGS. 5A, 5B, and 5C display schematics of different substrategeometries.

FIG. 6 illustrates a flow diagram of a method for making a thin filmoptical element.

DETAILED DESCRIPTION

It should be understood at the outset that although an illustrativeimplementation of one or more embodiments are provided below, thedisclosed systems and/or methods may be implemented using any number oftechniques, whether currently known or in existence. The disclosureshould in no way be limited to the illustrative implementations,drawings, and techniques below, including the exemplary designs andimplementations illustrated and described herein, but may be modifiedwithin the scope of the appended claims along with their full scope ofequivalents.

In the drawings and description that follow, like parts are typicallymarked throughout the specification and drawings with the same referencenumerals, respectively. In addition, similar reference numerals mayrefer to similar components in different embodiments disclosed herein.The drawing figures are not necessarily to scale. Certain features ofthe disclosed embodiments may be shown exaggerated in scale or insomewhat schematic form and some details of conventional elements maynot be shown in the interest of clarity and conciseness. The presentdisclosure is susceptible to embodiments of different forms. Specificembodiments are described in detail and are shown in the drawings, withthe understanding that the present disclosure is not intended to belimited to the embodiments illustrated and described herein. It is to befully recognized that the different teachings of the embodimentsdiscussed herein may be employed separately or in any suitablecombination to produce desired results.

Disclosed herein are systems for making thin film optical elements. Inan embodiment, a system for making a thin film optical element cancomprise (i) a thin film optical element comprising a substrate and afirst thin film stack, wherein the first thin film stack is deposited ona first deposition side of the substrate; wherein the first thin filmstack comprises two or more film layers; wherein the first thin filmstack is characterized by a first uniform film thickness; and whereinthe first uniform film thickness is defined as a thickness variation ofless than about +5% in any 10 mm² of the first thin film stack, whencompared to an average first thin film stack thickness across the entirefirst thin film stack; (ii) a holder comprising at least one holderopening; wherein the holder has a holder outer side and a holder innerside; wherein the holder outer side has at least one beveled edgeextending into a lip; wherein the beveled edge and the lip define the atleast one holder opening; wherein the lip has a substantially flat sideand a beveled edge side; wherein the beveled edge and/or the bevelededge side of the lip form an angle of less than about 45° with thesubstantially flat side of the lip and/or the first deposition side;wherein the substantially flat side of the lip and the holder inner sidedefine a holder socket; wherein the holder is configured to receive thesubstrate in the holder socket; wherein the holder opening is configuredto expose the first deposition side of the substrate to a depositionplume; wherein a portion of the first deposition side of the substratecontacts the substantially flat side of the lip, thereby allowing forthe first thin film stack to be deposited on the first deposition sideof the substrate; and wherein the beveled edge side of the lip and/orthe beveled edge provide for the first uniform film thickness of thefirst thin film stack; and (iii) a deposition source configured toprovide the deposition plume for depositing the first thin film stack onthe first deposition side of the substrate; wherein the deposition plumetravels towards the first deposition side of the substrate at adirection substantially perpendicular to the substantially flat side ofthe lip and/or to the first deposition side of the substrate; andwherein the beveled edge side of the lip faces the deposition plume.

Further disclosed herein are methods of making thin film opticalelements. In an embodiment, a method of making a thin film opticalelement can comprise (a) placing a substrate in a holder socket of aholder as disclosed herein; and (b) depositing, with a deposition plume,a first thin film stack on a first deposition side of the substrate toform a thin film optical element, wherein the thin film optical elementcomprises the substrate and the first thin film stack deposited on thefirst deposition side of the substrate; wherein the first thin filmstack comprises two or more film layers; wherein the first thin filmstack is characterized by a first uniform film thickness; and whereinthe first uniform film thickness is defined as a thickness variation ofless than about +5% in any 10 mm² of the first thin film stack, whencompared to an average first thin film stack thickness across the entirefirst thin film stack. In such embodiment, the method of making a thinfilm optical element can further exclude modifying the size of the thinfilm optical element. For example, the substrate can be sized to atarget size prior to depositing the first thin film stack on thesubstrate.

In some embodiments, for example as depicted in FIGS. 1-4, a holder 100as disclosed herein can comprise at least one holder opening 110. FIG. 1displays a schematic of a holder 100. FIGS. 2, 3, and 4 displayschematics of systems 200, 300, and 400, respectively for making a thinfilm optical element 205. FIGS. 5A, 5B, and 5C display schematics ofdifferent geometries for substrate 100. Referring to FIG. 6, a method2000 of making a thin film optical element is illustrated.

In an embodiment, a method 2000 of making a thin film optical element asdisclosed herein can comprise placing 2100 a substrate 210 in a holdersocket 150 of a holder 100.

In some embodiments, the holder 100 may comprise a plurality of holderopenings 110. The holder 100 may comprise from about 1 to about 100,alternatively from about 2 to about 75, or alternatively from about 5 toabout 75 holder openings 110, wherein each holder opening 110 isconfigured to receive a single substrate 210. The number of holderopenings 110 in the holder 100 dictates the number of substrates 210that can be used for making thin film optical elements concurrently. Forexample, when a holder 100 has 15 holder openings 110, the holder 100can receive at least 1 and up to and including 15 substrates 210 formaking at least 1 and up to and including 15 thin film optical elementsconcurrently; although any suitable number of substrates 210 equal to orless than 15 can be used in this case for making equal to or less than15 thin film optical elements concurrently.

In an embodiment, the holder 100 comprises a plurality of holderopenings 110; wherein the plurality of holder openings 110 provides forthe deposition of a thin film stack on a plurality of substrates 210;and wherein each holder opening 110 is configured to allow for thedeposition of a thin film stack on an individual substrate 210.

The holder opening 110 can have any suitable geometry. For example, theholder opening 110 can be circular. As another example, the holderopening 110 can be elliptical. As yet another example, the holderopening 110 can be characterized by irregular geometry. In someembodiments, all holder openings 110 of the same holder 100 can have thesame geometry (e.g., all holder openings 110 of the same holder 100 canbe circular; all holder openings 110 of the same holder 100 can beelliptical; all holder openings 110 of the same holder 100 can becharacterized by irregular geometry; etc.). In other embodiments, theholder openings 110 of the same holder 100 can have dissimilar geometry.For example, a portion of the holder openings 110 of the holder 100 canbe circular, while another portion of the holder openings 110 of thesame holder 100 can be elliptical, and while yet while another portionof the holder openings 110 of the same holder 100 can be characterizedby irregular geometry; thereby allowing for substrates 210 of varyinggeometries to be formed into thin film optical elements concurrently.

In some embodiments, for example as depicted in FIG. 1, a holder 100 asdisclosed herein can have a holder outer side 102 and a holder innerside 104; wherein the holder outer side 102 has at least one bevelededge 140 extending into a lip 130; and wherein the beveled edge 140 andthe lip 130 define the at least one holder opening 110. As will beappreciated by one of skill in the art, and with the help of thisdisclosure, each holder opening 110 of the holder 100 is individuallydefined by a beveled edge 140 and by a lip 130. In other words, theholder 100 has, on the holder outer side 102, an individual beveled edge140 extending into a lip 130 for each individual holder opening 110.

The lip 130 can have a substantially flat side 131 and a beveled edgeside 132. The substantially flat side 131 of the lip 130 faces about thesame direction as the holder inner side 104. The beveled edge side 132faces about the same direction as the beveled edge 140. In anembodiment, the beveled edge 140 and/or the beveled edge side 132 forman angle 135 of less than about 45°, alternatively less than about 40°,alternatively less than about 35°, alternatively less than about 30°,alternatively less than about 25°, alternatively less than about 20°, oralternatively less than about 15° with the substantially flat side 131of the lip 130.

The lip 130 is characterized by a terminal edge 136 that further definesthe holder opening 110. In some embodiments, the terminal edge 136 canbe a sharp terminal edge 145, for example as depicted in FIGS. 1 and 3.In other embodiments, the terminal edge 136 can be a blunted terminaledge 240, for example as depicted in FIG. 2. The blunted terminal edgemay be provided for safety and/or convenience. In yet other embodiments,the terminal edge 136 can be a deflecting terminal edge 440, for exampleas depicted in FIG. 4. The shape of the terminal edge 136 can influencethe uniformity of the film or film stack deposited on the substrate 210,as will be described in more detail later herein.

In some embodiments, all terminal edges 136 within the same holder 100can have the same geometry (e.g., all terminal edges 136 within the sameholder 100 can be sharp; all terminal edges 136 within the same holder100 can be blunted; all terminal edges 136 within the same holder 100can be deflecting; etc.). In other embodiments, the terminal edges 136within the same holder 100 can have dissimilar geometry. For example, aportion of the terminal edges 136 within the holder 100 can be sharp,while another portion of the terminal edges 136 within the same holder100 can be blunted, and while yet while another portion of the terminaledges 136 within the same holder 100 can be deflecting; thereby allowingfor tuning the deposition of the film and/or film stack on the substrate210.

The substantially flat side 131 of the lip 130 and the holder inner side104 define a holder socket 150, for example as depicted in FIGS. 1-4,wherein the holder 100 is configured to receive the substrate 210 in theholder socket 150. As will be appreciated by one of skill in the art,and with the help of this disclosure, each holder 100 has the samenumber of holder openings 110 and holder sockets 150, wherein eachholder opening 110 has a corresponding holder socket 150 that receiveseach substrate 210. For example, when a holder 100 has 21 holderopenings 110, the same holder 100 also has 21 holder sockets 150 thatare available to receive up to and including 21 individual substrates210 for making up to and including 21 thin film optical elementsconcurrently.

In some embodiments, the substantially flat side 131 of the lip 130 canbe characterized by a dimension (d) of less than about 10 mm,alternatively less than about 5 mm, alternatively less than about 5 mm,alternatively less than about 4 mm, alternatively less than about 3 mm,alternatively less than about 2 mm, alternatively less than about 1 mm,alternatively less than about 0.9 mm, alternatively less than about 0.8mm, alternatively less than about 0.7 mm, alternatively less than about0.6 mm, or alternatively less than about 0.5 mm. For purposes of thedisclosure herein, the dimension (d) of the substantially flat side 131of the lip 130 refers to the shortest distance between the terminal edge136 and an inner wall 151 of the holder socket 150.

In some embodiments, the lip 130 can further comprise one or morelocating holes 138, for example as depicted in FIG. 3. The lip 130 cancomprise any suitable distinctive marking device (e.g., locating hole138, a marking pin, etc.) that can mark the substrate 210 on its margin.For example, marking the substrate can enable visually identifying acoated side of the substrate (e.g., to prevent depositing a film or filmstack on the top of another film stack, as opposed to depositing a filmor film stack on the other side of the substrate).

The holder 100 can be made from any suitable material, for examplesteel, stainless steel, etc.

In some embodiments, for example as depicted in FIGS. 2-4, the holder100 can receive the substrate 210 in the holder socket 150. Thesubstrate 210 can have a first deposition side 220, wherein the holderopening 110 is configured to expose the first deposition side 220 of thesubstrate 210 to a deposition plume 250, 433, 435; wherein a portion ofthe first deposition side 220 of the substrate 210 contacts (e.g., restson) the substantially flat side 131 of the lip 130, thereby allowing fora first thin film stack 230 to be deposited by the deposition plume 250,433, 435 on the first deposition side 220 of the substrate 210. Thesubstrate 210 can have a second deposition side 225 spatially opposed tothe first deposition side 220.

In an embodiment, the substrate 210 comprises an optically transparentmaterial. Generally, a transparent or optically transparent materialallows light to pass through the material without being scattered.Typically, transparency can be assessed visually, or by opticalmicroscopy. Nonlimiting examples of optically transparent materialssuitable for use in the present disclosure in the substrate 210 includeglass, optically transparent glass, silica, sapphire, silicon,germanium, zinc selenide, zinc sulfide, polycarbonate,polymethylmethacrylate (PMMA), polyvinylchloride (PVC), diamond,ceramics, and the like, or combinations thereof. Further, and as will beappreciated by one of skill in the art, and with the help of thisdisclosure, the material that the substrate is made of can withstandfilm deposition conditions, such as elevated temperatures, vacuum, etc.

The substrate 210 can have any suitable geometry. Generally, thegeometry of the substrate 110 (i.e., holder socket 150) matches thegeometry of the substrate 210. In an embodiment, the substrate 210 canbe sized to a desired shape and size (e.g., target shape and/or targetsize) prior to placing the substrate 210 in the holder socket 150 of theholder 100 (i.e., prior to depositing a film or film stack on thesubstrate 210). The substrate 210 can be sized to a desired shape andsize by using any suitable methodology such as coring, cutting,cleaving, grinding, polishing, and the like, or combinations thereof.

In some embodiments, the first deposition side 220 and the seconddeposition side 225 of the substrate 210 are substantially parallel toeach other. For example, the substrate 210 can be a cylinder (e.g.,circular cylinder, elliptical cylinder, circular disc, elliptical disc,etc.). In such embodiments, the first deposition side 220 and the seconddeposition side 225 can be the same (e.g., can have the same size andshape).

In other embodiments, the first deposition side 220 and the seconddeposition side 225 of the substrate 210 are not parallel to each other.In such embodiments, the first deposition side 220 and the seconddeposition side 225 can be different (e.g., can have different sizeand/or shape).

The size of the first deposition side 220 and/or the second depositionside 225 of the substrate 210 can be less than about 0.5 inches (12.7mm), alternatively less than about 0.25 inches (6.4 mm), oralternatively less than about 0.1 inches (2.5 mm). For purposes of thedisclosure herein, the size of the first deposition side 220 and/or thesecond deposition side 225 of the substrate 210 refers to the longestdimension of the first deposition side 220 and/or the second depositionside 225, respectively. For example, when the first deposition side 220and/or the second deposition side 225 are circular, the size of thefirst deposition side 220 and/or the second deposition side 225 refersto the diameter of the first deposition side 220 and/or the seconddeposition side 225, respectively. As another example, when the firstdeposition side 220 and/or the second deposition side 225 areelliptical, the size of the first deposition side 220 and/or the seconddeposition side 225 refers to the diameter along the major axis (e.g.,the length of the major axis) of the first deposition side 220 and/orthe second deposition side 225, respectively.

In some embodiments, the first deposition side 220 and/or the seconddeposition side 225 of the substrate 210 can be substantially flat orplanar. In such embodiments, the first deposition side 220 and/or thesecond deposition side 225 of the substrate 210 can be substantiallyparallel to the substantially flat side 131 of the lip 130. When amating holder 301 is employed, as will be described in more detail laterherein, the first deposition side 220 and/or the second deposition side225 of the substrate 210 can be substantially parallel to asubstantially flat side 331 of a lip 330 of the mating holder 301.

In other embodiments, the first deposition side 220 and/or the seconddeposition side 225 of the substrate 210 can be rugged (as opposed toflat).

In some embodiments, the first deposition side 220 and/or the seconddeposition side 225 can be circular 510, for example as depicted in FIG.5A. The cross-section of the substrate depicted in FIG. 5A indicatesthat the diameter (D) is regular (D1=D2).

In other embodiments, the first deposition side 220 and/or the seconddeposition side 225 can be elliptical 520, for example as depicted inFIG. 5B. The cross-section of the substrate depicted in FIG. 5Bindicates that the diameter (D) varies across the cross-section (D1≠D2).

In yet other embodiments, the first deposition side 220 and/or thesecond deposition side 225 can be characterized by irregular geometry530, for example as depicted in FIG. 5C. The cross-section of thesubstrate depicted in FIG. 5C indicates that the diameter (D) variesacross the cross-section (D1≠D2≠Di≠D1).

In some embodiments, a distance between the first deposition side 220and the second deposition side 225 of the substrate 210 can be less thanthe size of the first deposition side 220 and/or the size of the seconddeposition side 225. For example, in the case of a circular cylindricalsubstrate, the height of the cylinder is less than the diameter of thecross-section of the cylinder; wherein the substrate 210 is a disc.

In other embodiments, a distance between the first deposition side 220and the second deposition side 225 of the substrate 210 can be equal toor greater than the size of the first deposition side 220 and/or thesize of the second deposition side 225. For example, in the case of acircular cylindrical substrate, the height of the cylinder is equal toor greater than the diameter of the cross-section of the cylinder.

In some embodiments, for example as depicted in FIG. 3, a mating holder301 can be placed on the substrate 210 and holder 100, wherein themating holder 301 contacts the substrate 210 and the holder 100.

The mating holder 301 can help secure the substrate 100 in place forfilm deposition. For example, the mating holder 301 can provide forsecuring the substrate 210 in place for the deposition of a first thinfilm stack 230 on the first deposition side 220 of the substrate 210,the deposition of the second thin film stack 231 on the seconddeposition side 225 of the substrate 210, or both the deposition of thefirst thin film stack 230 on the first deposition side 220 of thesubstrate 210 and the deposition of the second thin film stack 231 onthe second deposition side 225 of the substrate 210.

Further, the mating holder 301 can provide for spatially rotating (e.g.,flipping, inverting, etc.) the substrate 210 such that the desireddeposition side faces the deposition plume. For example, the holder 100and the mating holder 301 can be configured to spatially rotate thesecured substrate 210 to provide for the deposition plume 250, 433, 435traveling towards the first deposition side 220 or the second depositionside 225 of the substrate 210 (as desired) at a direction substantiallyperpendicular to the first deposition side 220 or the second depositionside 225, respectively.

In some embodiments, the holder 100 and the mating holder 301 can be thesame (e.g., can have the same size and shape). In other embodiments, theholder 100 and the mating holder 301 can be different (e.g., can havedifferent size and/or shape).

The mating holder 301 comprises at least one mating holder opening 310.In some embodiments, the mating holder 301 may comprise a plurality ofmating holder opening 310. The mating holder 301 may comprise from about1 to about 100, alternatively from about 2 to about 75, or alternativelyfrom about 5 to about 75 mating holder opening 310, wherein each matingholder opening 310 is configured to receive a single substrate 210. Thenumber of mating holder openings 310 in the mating holder 301 matchesthe number of holder openings 110 in the holder 100.

In an embodiment, the mating holder 301 comprises a plurality of matingholder openings 310; wherein the plurality of mating holder openings 310provides for the deposition of a thin film stack on a plurality ofsubstrates 210; and wherein each mating holder opening 310 is configuredto allow for the deposition of a thin film stack on an individualsubstrate 210.

The mating holder 301 has a mating holder outer side 302 and a matingholder inner side 304; wherein the mating holder inner side 304 contactsthe holder inner side 104; wherein the mating holder outer side 302 hasat least one beveled edge 340 extending into a lip 330; wherein thebeveled edge 340 and the lip 330 define the at least one mating holderopening 310; wherein the lip 330 has a substantially flat side 331 and abeveled edge side 332; wherein the beveled edge 340 and/or the bevelededge side 332 form an angle 335 of less than about 45°, alternativelyless than about 40°, alternatively less than about 35°, alternativelyless than about 30°, alternatively less than about 25°, alternativelyless than about 20°, or alternatively less than about 15° with thesubstantially flat side 331 of the lip 330 and/or the second depositionside 225.

The lip 330 is characterized by a terminal edge that further defines themating holder opening 310. In some embodiments, the terminal edge of thelip 330 can be a sharp terminal edge 345, for example as depicted inFIG. 3. In other embodiments, the terminal edge of the lip 330 can be ablunted terminal edge. In yet other embodiments, the terminal edge ofthe lip 330 can be a deflecting terminal edge. The shape of the terminaledge of the lip 330 can influence the uniformity of the film or filmstack deposited on the substrate 210, as will be described in moredetail later herein.

In some embodiments, all terminal edges within the same mating holder301 can have the same geometry (e.g., all terminal edges within the samemating holder 301 can be sharp; all terminal edges within the samemating holder 301 can be blunted; all terminal edges within the samemating holder 301 can be deflecting; etc.). In other embodiments, theterminal edges within the same mating holder 301 can have dissimilargeometry. For example, a portion of the terminal edges within the matingholder 301 can be sharp, while another portion of the terminal edgeswithin the same mating holder 301 can be blunted, and while yet whileanother portion of the terminal edges within the same mating holder 301can be deflecting; thereby allowing for tuning the deposition of thefilm and/or film stack on the substrate 210.

The substantially flat side 331 of the lip 330 and the mating holderinner side 304 define a mating holder socket 350; wherein the matingholder 301 is configured to receive the substrate 210 in the matingholder socket 350; wherein the mating holder opening 310 is configuredto expose the second deposition side 225 of the substrate 210 to thedeposition plume 250, 433, 435; and wherein a portion of the seconddeposition side 225 of the substrate 210 contacts the substantially flatside 331 of the lip 330, thereby allowing for the second thin film stack231 to be deposited on the second deposition side 225 of the substrate210.

As will be appreciated by one of skill in the art, and with the help ofthis disclosure, when a mating holder is not present or used, thesubstrate 210 can be secured by any suitable method in the holder 100(e.g., the substrate 210 can be clamped in the holder 100).

In an embodiment, a method 2000 of making a thin film optical element asdisclosed herein can comprise depositing 2200, with a deposition plume250, 433, 435, a first thin film stack 230 on the first deposition side220 of the substrate 210 to form a thin film optical element 205,wherein the thin film optical element 205 comprises the substrate 210and the first thin film stack 230 deposited on the first deposition side220 of the substrate 210. In such embodiment, the holder opening 110exposes the first deposition side 220 of the substrate 210 to thedeposition plume 250, 433, 435.

The deposition plume 250, 433, 435 can travel towards the firstdeposition side 220 of the substrate 210 at a direction substantiallyperpendicular to the substantially flat side 131 of the lip 130 and/orto the first deposition side 220; wherein the beveled edge side 132 ofthe lip 130 faces the deposition plume 250, 433, 435; and wherein theholder opening 110 exposes the first deposition side 220 to thedeposition plume 250, 433, 435.

In some embodiments, the method 2000 of making a thin film opticalelement as disclosed herein can further comprise inverting 2300 thesubstrate 210 in the holder socket 150 subsequent to depositing 2200 thefirst thin film stack 230; wherein the holder opening 110 exposes thesecond deposition side 225 of the substrate 210 to the deposition plume250, 433, 435 as disclosed herein.

The deposition plume 250, 433, 435 can travel towards the seconddeposition side 225 of the substrate 210 at a direction substantiallyperpendicular to the substantially flat side 131 of the lip 130 and/orto the first deposition side 220; wherein the beveled edge side 132 ofthe lip 130 faces the deposition plume 250, 433, 435; and wherein theholder opening 110 exposes the second deposition side 225 to thedeposition plume 250, 433, 435.

In other embodiments, the method 2000 of making a thin film opticalelement as disclosed herein can further comprise inverting 2400 thesubstrate 210 secured in the holder 100 and the mating holder 301subsequent to depositing 2200 the first thin film stack 230; wherein themating holder opening 310 exposes the second deposition side 225 of thesubstrate 210 to the deposition plume 250, 433, 435 as disclosed herein.

The deposition plume 250, 433, 435 can travel towards the seconddeposition side 225 of the substrate 210 at a direction substantiallyperpendicular to the substantially flat side 331 of the lip 330 and/orto the second deposition side 225; wherein the beveled edge side 332 ofthe lip 330 faces the deposition plume 250, 433, 435; and wherein theholder opening 310 exposes the second deposition side 225 to thedeposition plume 250, 433, 435.

Generally, the substrate 210, holder 100, and optionally mating holder301, as well as a deposition source (and consequently the depositionplume 250, 433, 435) are located inside a deposition chamber. In anembodiment, the thin film stacks 230, 231 can be deposited on thesubstrate by using any suitable methodology, such as any suitablephysical vapor deposition (PVD) or chemical vapor deposition (CVD)technique. In the case of CVD techniques, the material to be depositedreacts with a gaseous environment of co-depositing material to form afilm of a new material that results from a chemical reaction (e.g., anitride, an oxide, a carbide, a carbonitride, etc.). Nonlimitingexamples of CVD techniques include atmospheric pressure CVD,metal-organic CVD, low pressure CVD, laser CVD, photo-CVD, chemicalvapor infiltration, chemical beam epitaxy, plasma-assisted CVD,plasma-enhanced CVD, and the like, or combinations thereof.

Generally, PVD refers to a collection of vaporization coating techniquesin which a material is atomically transferred from solid phase (e.g.,deposition source) to vapor phase (e.g., vapor of material to bedeposited forming the deposition plume 250, 433, 435) and back to thesolid phase (e.g., thin film), gradually building a film on the surfaceto be coated (e.g., first deposition side 220, second deposition side225).

In PVD, the layers of the thin film stacks 230, 231 are formed bycondensation of vaporized material from the deposition source, whilemaintaining a vacuum in the deposition chamber. An example of a PVDtechnique is electron beam (E-beam) deposition, in which a beam of highenergy electrons (i.e., electron beam) is electromagnetically focusedonto the material(s) of the deposition source(s), to evaporate atomicspecies. In some embodiments, E-beam deposition can be assisted by ions,provided by ion-sources, to clean or etch the substrate 210; and/or toincrease the energy of the evaporated material(s), such that theevaporated material(s) is deposited onto the substrate 210 more densely,for example. Other nonlimiting examples of PVD techniques that can beused to form the thin film stacks 230, 231 include cathodic arcdeposition (in which an electric arc discharged at the material(s) ofthe deposition source(s) blasts away some material(s) into ionized vaporto be deposited onto the substrate 210); evaporative deposition (inwhich material(s) included of the deposition source(s) is heated to ahigh vapor pressure by electrically resistive heating); pulsed laserdeposition (in which a laser ablates material(s) from the depositionsource(s) into vapor phase); sputter deposition (in which a glow plasmadischarge—usually localized around the deposition source(s) by amagnet—bombards the material(s) of the source(s) sputtering some of thematerial(s) away as a vapor); and the like; or combinations thereof.

In an embodiment, a method 2000 of making a thin film optical element asdisclosed herein excludes modifying the size of the thin film opticalelement 205. The substrate 210 can be sized to a target size and/orshape prior to depositing the thin film stack 230, 231 on the substrate210. The size of the first deposition side 220 of the substrate 210 isnot modified subsequent to the first thin film stack 230 being depositedon the first deposition side 220 of the substrate 210. Similarly, thesize of the second deposition side 225 of the substrate 210 is notmodified subsequent to the second thin film stack 231 being deposited onthe second deposition side 225 of the substrate 210.

In an embodiment, the first deposition side 220 and/or the seconddeposition side 225 of the substrate 210 (e.g., the surface of the firstdeposition side 220 and/or the second deposition side 225) can beprocessed or prepared prior to depositing the thin film stack 230, 231on the substrate 210. Preparing the first deposition side 220 and/or thesecond deposition side 225 of the substrate 210 may include reducing thethickness of the substrate 210 until a desired or predeterminedthickness of the substrate 210 is achieved. In some embodiments, thethickness of the substrate 210 may be reduced through chemical means,such as etching, oxidation, etc. In other embodiments, the thickness ofthe substrate 210 may be reduced through physical means, such ascutting, cleaving, grinding, polishing, etc.

In some embodiments, the first deposition side 220 and/or the seconddeposition side 225 of the substrate 210 may include chemically treatingthe surface of the substrate 210 so that it becomes more amenable orreceptive to a particular thin film deposition process. For example,some thin film deposition techniques can be surface selective. In otherwords, some of the materials used to build the layers of the thin filmstack 230, 231 may not chemically bond or otherwise adhere to a givensubstrate 210 surface. To accommodate layer chemistries that may notdirectly adhere to a given substrate 210, the surface of the substrate210 may be coated or otherwise pre-treated with a reactive agent, suchas aluminum, titanium, silicon, germanium, indium, gallium, arsenic,etc. Coating the surface of the substrate 210 with a reactive agent maybe done using any suitable sputtering techniques. The reactive agent maythen be reacted in order to generate an oxide surface that may be moreresponsive to various thin film deposition techniques. In otherembodiments, the surface of the substrate 210 may be treated with anoxidation product to promote adherence of thin layers.

In an embodiment, a method 2000 of making a thin film optical element asdisclosed herein can comprise depositing 2500, with a deposition plume250, 433, 435, a second thin film stack 231 on the second depositionside 225 of the substrate 210 to form the thin film optical element 205,wherein the thin film optical element 205 comprises the substrate 210,the first thin film stack 230 deposited on the first deposition side 220of the substrate 210, and the second thin film stack 231 deposited onthe second deposition side 225 of the substrate 210.

In some embodiments, the substrate 210 can be inverted 2300 (e.g.,rotated, flipped, etc.) in the holder socket 150 subsequent todepositing the first thin film stack 230; wherein the holder opening 110exposes the second deposition side 225 of the substrate 210 to thedeposition plume 250, 433, 435; and wherein a portion of the seconddeposition side 225 of the substrate 210 contacts the substantially flatside 131 of the lip 130.

In embodiments where a mating holder 301 contacts the holder 100 and thesubstrate 210 and provides for securing the substrate 210 in place forthin film deposition as previously described herein, the substrate 210secured in the holder 100 and the mating holder 301 can be inverted 2400subsequent to depositing the first thin film stack 230, wherein themating holder opening 310 exposes the second deposition side 225 of thesubstrate 210 to the deposition plume 250, 433, 435. As will beappreciated by one of skill in the art, and with the help of thisdisclosure, in such embodiments, inverting the substrate 210 secured inthe holder 100 and the mating holder 301 entails inverting the wholeassembly comprising the substrate 210, as well as the holder 100 and themating holder 301 that secure the substrate 210 in place for thin filmdeposition.

In an embodiment, the thin film optical element 205 as disclosed hereincan comprise the substrate 210 and the first thin film stack 230,wherein the first thin film stack 230 is deposited on the firstdeposition side 220 of the substrate 210; wherein the first thin filmstack 230 comprises two or more film layers; wherein the first thin filmstack 230 is characterized by a first uniform film thickness; andwherein the first uniform film thickness is defined as a thicknessvariation of less than about ±5%, alternatively less than about ±4%,alternatively less than about ±3%, alternatively less than about ±2%,alternatively less than about ±1%, alternatively less than about ±0.5%,or alternatively less than about ±0.1% in any 10 mm² of the first thinfilm stack 230, when compared to an average first thin film stackthickness across the entire first thin film stack 230. Film thicknessand/or film thickness uniformity (e.g., first film thickness, secondfilm thickness, first film thickness uniformity, second film thicknessuniformity) can be determined by using any suitable methodology, such asellipsometry, transmission spectroscopy, reflection spectroscopy, thinfilm profilometry, x-ray reflectivity, cross-sectional scanning electronmicroscopy, cross-sectional tunneling electron microscopy, and the like,or combinations thereof.

In an embodiment, the thin film optical element 205 as disclosed hereincan further comprise a second thin film stack 231, wherein the secondthin film stack 231 is deposited on the second deposition side 225 ofthe substrate 210; wherein the second thin film stack 231 comprises twoor more film layers; wherein the second thin film stack 231 ischaracterized by a second uniform film thickness; wherein the seconduniform film thickness is defined as a thickness variation of less thanabout ±5%, alternatively less than about ±4%, alternatively less thanabout ±3%, alternatively less than about ±2%, alternatively less thanabout ±1%, alternatively less than about ±0.5%, or alternatively lessthan about ±0.1% in any 10 mm² of the second thin film stack 231, whencompared to an average second thin film stack thickness across theentire second thin film stack 231.

In an embodiment, each of the first thin film stack 230 and/or thesecond thin film stack 231 can be independently characterized by athickness of from about 1 nm to about 10 μm, alternatively from about 50nm to about 7.5 μm, or alternatively from about 100 nm to about 5 μm.

In an embodiment, each of the first thin film stack 230 and the secondthin film stack 231 can independently comprise a plurality of layers(e.g., thin film layers). For example, each of the first thin film stack230 and the second thin film stack 231 can independently comprise fromabout 2 to about 50 layers, alternatively from about 5 to about 35layers, or alternatively from about 7 to about 25 layers.

In an embodiment, each layer of the first thin film stack 230 and/or thesecond thin film stack 231 can be independently characterized by athickness of from about 0.5 nm to about 2 μm, alternatively from about0.75 nm to about 1.5 μm, or alternatively from about 1 nm to about 1 μm.In some embodiments, all layers of the first thin film stack 230 and/orthe second thin film stack 231 can have the same thickness. In otherembodiments, some layers of the first thin film stack 230 and/or thesecond thin film stack 231 can have the same thickness, while otherlayers of the first thin film stack 230 and/or the second thin filmstack 231 can have different thickness.

In an embodiment, each layer of the first thin film stack 230 and/or thesecond thin film stack 231 can independently comprise silicon (Si),niobium (Nb), germanium (Ge), binary oxides, quartz, silica (SiO₂),niobia (Nb₂O₅), germania (GeO₂), magnesium fluoride (MgF₂), titania(TiO₂), alumina (Al₂O₃), hafnium dioxide (HfO₂), ternary oxides, and thelike, or combinations thereof.

In an embodiment, the initial or first layer deposited on the firstdeposition side 220 and/or the second deposition side 225 of thesubstrate 210 may be made of a metal oxide material, such as aluminumoxide (Al₂O₃), titanium dioxide (TiO₂), etc. As will be appreciated byone of skill in the art, and with the help of this disclosure, the oxidematerial of the first layer may prove advantageous in creating a goodadhesion to the substrate 210, thereby protecting the thin films frominadvertent removal from the substrate 210. In some embodiments, one orboth of the first and last layers of the first thin film stack 230and/or the second thin film stack 231 may be deposited to a thicknessthat is greater than the other interposing layers (i.e., the layersdisposed between the first deposited layer and the last deposited layerof a film stack; intermediate layers). As will be appreciated by one ofskill in the art, and with the help of this disclosure, providingthicker first and/or last layers may provide increased mechanicalstrength to the thin film optical element 205.

In an embodiment, any two adjacent layers of the first thin film stack230 and/or the second thin film stack 231 can be characterized by adifferent refraction index from each other. The thin film opticalelement 205 as disclosed herein can comprise a plurality of thin filmlayers consisting of various materials whose indices of refraction andsize (e.g., thickness) may vary between each layer. The thin film layersmay be deposited on the substrate so as to selectively passpredetermined fractions of electromagnetic radiation at differentwavelengths configured to substantially mimic a regression vectorcorresponding to a particular physical or chemical property of interestof a substance of interest. In some embodiments, an individual thin filmoptical element 205 as disclosed herein can exhibit a specifictransmission function that is tailored or weighted with respect towavelength. As a result, an output light intensity from an integratedcomputational element (ICE) comprising the thin film optical element 205conveyed to a detector may be related to a physical or chemical propertyof interest for the substance of interest.

As will be appreciated by one of skill in the art, and with the help ofthis disclosure, errors in fabrication of the constituent layers of athin film optical element 205 can negatively impact the performance ofthe thin film optical element 205. In some instances, deviations of<0.1%, and even 0.01% or 0.0001% from complex indices of refraction,and/or thicknesses of the formed layers of the thin film optical element205 can substantially impact the performance of the thin film opticalelement 205, in some cases to such an extent, that the thin film opticalelement 205 may become operationally useless. Further, and as will beappreciated by one of skill in the art, and with the help of thisdisclosure, depositing uniform thickness layers that lead to uniformthickness thin film stacks is important for the performance of thin filmoptical element 205 as disclosed herein.

In an embodiment, the beveled edge side 132 of the lip 130 and/or thebeveled edge 140 can provide for the first uniform film thickness of thefirst thin film stack 230 and/or the second uniform film thickness ofthe second thin film stack 231. In an embodiment, the beveled edge side332 of the lip 330 and/or the beveled edge 340 can provide for thesecond uniform film thickness of the second thin film stack 231. Thesteep angle 135, 335 (e.g., low angle with respect to the holder innerside 104 and/or mating holder inner side 304) provides for reducing orminimizing shadowing effects and/or edge effects of the holder 100and/or mating holder 301 masking the deposition plume 250, 433, 435 nearthe edges of the holder opening 110 and/or mating holder opening 310. Ifthe angle 135, 335 would be greater than 45°, for example a 90° angle,the deposition plume would hit the edge 140, 340 of the holder/matingholder much sooner, by providing a physical obstacle in the path of thedeposition plume 250, 433, 435, which would lead to a shadowing effectand/or edge effect. Generally, edge effects refer to the non-uniformfilm deposition near the edges, e.g., non-uniform film deposition on thesubstrate 210 near the holder opening 110 and/or mating holder opening310.

In an embodiment, the beveled edge 140 of the holder 100 and/or thebeveled edge side 132 of the lip 130 of the holder 100 can becharacterized by a geometry effective for minimizing edge effects of agiven deposition plume spatial profile. The value of the angle 135between (i) the substantially flat side 131 of the lip 130, the firstdeposition side 220 of the substrate 210, the second deposition side 225of the substrate 210, or combinations thereof, and (ii) the beveled edgeside 132 of the lip 130 and/or the beveled edge 140 of the holder 100can be effective for minimizing edge effects of a given deposition plumespatial profile. For example, the angle 135 can be less than about 45°,alternatively less than about 40°, alternatively less than about 35°,alternatively less than about 30°, alternatively less than about 25°,alternatively less than about 20°, or alternatively less than about 15°.

In an embodiment, the beveled edge 340 of the mating holder 301 and/orthe beveled edge side 332 of the lip 330 of the mating holder 301 can becharacterized by a geometry effective for minimizing edge effects of agiven deposition plume spatial profile. The value of the angle 335between (i) the substantially flat side 331 of the lip 330 and/or thesecond deposition side 225 of the substrate 210, and (ii) the bevelededge side 332 of the lip 330 and/or the beveled edge 340 of the matingholder 301 can be effective for minimizing edge effects of a givendeposition plume spatial profile. For example, the angle 335 can be lessthan about 45°, alternatively less than about 40°, alternatively lessthan about 35°, alternatively less than about 30°, alternatively lessthan about 25°, alternatively less than about 20°, or alternatively lessthan about 15°.

FIG. 4 illustrates the effects of various types of edges outlining theholder opening 110 in the system 400 for making a thin film opticalelement 205.

In the case of the deflecting terminal edge 440, the deposition plume433 provides for a well-directed coating material, wherein thedeflecting terminal edge 440 provides for a deflection path 434 thatdeflects excess material away from the first deposition side 220 of thesubstrate 210, thereby leading to a tuned edge 450 of the first thinfilm stack 230, as well as an uniform middle coating 460 of the firstthin film stack 230.

In the case of the severely blunted edge 441, the deposition plume 435provides for a coating material that is less well directed than thecoating material near the deflecting terminal edge 440, wherein theseverely blunted edge 441 provides for a deflection path 436 thatdeflects excess material towards the first deposition side 220 of thesubstrate 210, thereby leading to an increased edge deposition 470 whichresults in a non-uniform thin film. As will be appreciated by one ofskill in the art, and with the help of this disclosure, increased edgedeposition 470 is one example of an edge effect during thin filmdeposition.

The deposition plume 250, 433, 435 can be tuned (e.g., adjusted,modulated, etc.) in accordance with the geometry of the beveled edgebordering the holder opening 110 or the mating holder opening 310. Forexample, a spatial profile of the deposition plume 250, 433, 435 can betuned in accordance with the geometry of the beveled edge 140 and/or thegeometry of the beveled edge side 132 of the lip 130 to provide forminimizing edge effects during depositing the first thin film stack 230and/or the second thin film stack 231. As another example, a spatialprofile of the deposition plume 250, 433, 435 can be tuned in accordancewith the geometry of the beveled edge 340 and/or the geometry of thebeveled edge side 332 of the lip 330 to provide for minimizing edgeeffects during depositing the second thin film stack 231.

Without wishing to be limited by theory, a deposition plume 250, 433,435 can be placed in a three-dimensional Cartesian coordinate systemhaving axes x, y, and z. For example, the deposition plume 250, 433, 435can display a spatial profile (i.e., a three-dimensional spatialprofile) that has the same spatial symmetry relative to both x and yaxes; e.g., the spatial profile of the deposition plume 250, 433, 435can be a sphere (where the deposition plume can be provided by apoint-like deposition source). As another example, when the depositionplume 250, 433, 435 is provided by an extended deposition source (asopposed to a point-like deposition source), the deposition plume 250,433, 435 can display a Lambertian (cosine emission) spatial profiledistribution. Other examples of spatial profiles of the deposition plume250, 433, 435 can include a parabolic profile and/or a hyperbolicprofile.

In some embodiments, the spatial profile of the deposition plume 250,433, 435 can be tuned by focusing the deposition plume 250, 433, 435; bymasking the deposition plume 250, 433, 435; or both by focusing thedeposition plume 250, 433, 435 and by masking the deposition plume 250,433, 435. In such embodiments, an electron beam (e.g., assisted ionbeam) can contact a deposition source as previously described herein toproduce the deposition plume 250, 433, 435; wherein the spatial profileof the deposition plume 250, 433, 435 can be tuned by focusing theelectron beam, by masking the electron beam, or both by focusing theelectron beam and by masking the electron beam.

In an embodiment, a method 2000 of making a thin film optical element asdisclosed herein can comprise subjecting 2600 the thin film opticalelement 205 to quality control analysis, wherein the quality controlanalysis comprises at least one analytical technique selected from thegroup consisting of ellipsometry, reflectance spectroscopy, transmissionspectroscopy, and combinations thereof. In embodiments where thin filmstacks 230, 231 are deposited on both the first deposition side 220 andthe second deposition side 225 of the substrate 210, the thin filmoptical element 205 may be subjected 2600 to quality control analysissubsequent to depositing the first thin film stack 230 and prior todepositing the second thin film stack 231, in order to assess thequality of the first thin film stack 230. In such embodiments, the thinfilm optical element 205 may be further subjected 2600 to qualitycontrol analysis subsequent to depositing the second thin film stack231, in order to assess the quality of the second thin film stack 231.In such embodiments, the quality of the first thin film stack 230 may bereassessed subsequent to depositing the second thin film stack 231.

In some embodiments, the thin film optical element 205 may be subjected2600 to quality control analysis subsequent to depositing both the firstthin film stack 230 and the second thin film stack 231, in order toassess the quality of both the first thin film stack 230 and the qualityof the second thin film stack 231.

In an embodiment, the quality control analysis comprises ellipsometry toassess film thickness and uniformity of the first thin film stack 230and/or the second thin film stack 231.

In an embodiment, the quality control analysis comprises reflectancespectroscopy to assess a reflectance function of the thin film opticalelement 205.

In an embodiment, the quality control analysis comprises transmissionspectroscopy to assess a transmission function of the thin film opticalelement 205.

In some embodiments, the thin film optical element 205 can be used as anintegrated computational element (ICE). ICEs may enable the measurementof various chemical or physical characteristics of a substance throughthe use of regression techniques. For purposes of the disclosure herein,the terms “characteristic” or “characteristic of interest” refers to achemical, mechanical, or physical property of a substance or a sample ofthe substance. The characteristic of a substance may include aquantitative or qualitative value of one or more chemical constituentsor compounds present therein or any physical property associatedtherewith. Such chemical constituents and compounds may be referred toherein as “analytes.” Nonlimiting examples of characteristics of asubstance that can be analyzed with the help of the optical processingelements described herein (e.g., ICEs, such as thin film opticalelements 205) can include, for example, chemical composition (e.g.,identity and concentration in total or of individual components), phasepresence (e.g., gas, oil, water, etc.), impurity content, pH,alkalinity, viscosity, density, ionic strength, total dissolved solids,salt content (e.g., salinity), porosity, opacity, bacteria content,total hardness, transmittance, state of matter (e.g., solid, liquid,gas, emulsion, mixtures thereof, etc.), and the like, or combinationsthereof.

Further, for purposes of the disclosure herein, the term “substance”refers to at least a portion of matter or material of interest to betested or otherwise evaluated with the help of the optical processingelements described herein (e.g., ICEs, such as thin film opticalelements 205). The substance may be any fluid capable of flowing,including particulate solids, liquids, gases (e.g., air, nitrogen,carbon dioxide, argon, helium, methane, ethane, butane, and otherhydrocarbon gases, hydrogen sulfide, or combinations thereof), slurries,emulsions, powders, muds, glasses, mixtures, combinations thereof, andmay include, but is not limited to, aqueous fluids (e.g., water, brines,etc.), non-aqueous fluids (e.g., organic compounds, hydrocarbons, oil, arefined component of oil, petrochemical products, and the like), acids,surfactants, biocides, bleaches, corrosion inhibitors, foamers, foamingagents, breakers, scavengers, stabilizers, clarifiers, detergents,treatment fluids, fracturing fluids, formation fluids, or any oilfieldfluid, chemical, or compound commonly found in the oil and gas industry.The substance may also refer to solid materials such as, but not limitedto, rock formations, concrete, solid wellbore surfaces, pipes or flowlines, and solid surfaces of any wellbore tool or projectile (e.g.,balls, darts, plugs, etc.).

Generally, information about a substance can be derived through theinteraction of light with that substance (e.g., optical interaction);wherein such interaction can change characteristics of the light, forinstance the frequency (and corresponding wavelength), intensity,polarization, and/or direction (e.g., through scattering, absorption,reflection or refraction). Chemical, thermal, physical, mechanical,optical or various other characteristics of the substance can bedetermined based on the changes in the characteristics of the lightinteracting with the substance. Thus, one or more characteristics ofsubstances such as crude petroleum, gas, water, or other wellbore fluidscan be assessed in-situ, e.g., downhole at well sites, as a result ofthe interaction between these substances and light. For purposes of thedisclosure herein, the terms “optically interact” or “opticalinteraction” refer to the reflection, transmission, scattering,diffraction, or absorption of electromagnetic radiation either on,through, or from an optical processing element (e.g., ICE, such as athin film optical element 205) or a substance being analyzed with thehelp of the optical processing element. Accordingly, opticallyinteracted light refers to electromagnetic radiation that has beenreflected, transmitted, scattered, diffracted, or absorbed by, emitted,or re-radiated, for example, using an optical processing element, butmay also apply to optical interaction with a substance. Further, forpurposes of the disclosure herein, the term “electromagnetic radiation”refers to radio waves, microwave radiation, terahertz radiation,infrared and near-infrared radiation, visible light, ultraviolet light,X-ray radiation, gamma ray radiation, and the like.

An ICE can selectively weight (when operated as part of an opticalanalysis tool) light modified by a sample in at least a portion of awavelength range such that the weightings can be correlated to one ormore characteristics of the sample. An ICE can be an optical substratewith multiple stacked dielectric layers (e.g., from about 2 to about 50layers), each having a different complex refractive index from itsadjacent layers, for example the thin film optical element 205 asdisclosed herein. As will be appreciated by one of skill in the art, andwith the help of this disclosure, the specific number of layers in thethin film optical element 205, the optical properties of the layers, theoptical properties of the substrate, the thickness of each layer, etc.can be selected so that the light processed by the ICE is related to oneor more characteristics of the sample. Further, and as will beappreciated by one of skill in the art, and with the help of thisdisclosure, because ICEs extract information from the light modified bya sample passively, ICEs can be incorporated in low cost and ruggedoptical analysis tools. Hence, ICE-based downhole optical analysis toolscan provide a relatively low cost, rugged and accurate system formonitoring quality of wellbore fluids, for example.

In an embodiment, the ICE can be further employed 2700 in an opticalcomputing device. Optical computing devices, also commonly referred toas opticoanalytical devices, can be used to analyze and monitor a sampleor substance in real time. For purposes of the disclosure herein, theterm “optical computing device” refers to an optical device that isconfigured to receive an input of electromagnetic radiation associatedwith a substance and produce an output of electromagnetic radiation froman optical processing element (e.g., ICE, such as the thin film opticalelement 205) arranged within or otherwise associated with the opticalcomputing device. The electromagnetic radiation that optically interactswith the optical processing element is changed so as to be readable by adetector, such that an output of the detector can be correlated to aparticular characteristic of the substance being analyzed. The output ofelectromagnetic radiation from the optical processing element can bereflected, transmitted, and/or dispersed electromagnetic radiation.Whether the detector analyzes reflected, transmitted, or dispersedelectromagnetic radiation may be dictated by structural parameters ofthe optical computing device as well as other considerations known toone of skill in the art.

In some embodiments, the optical computing device can be employed 2700in a downhole tool in a wellbore penetrating a subterranean formation.For example, the downhole tool can be a well logging tool, wherein thewell logging tool can be configured as an ICE-based optical analysistool. As another example, the downhole tool can be a bottom holeassembly, a drilling assembly, a sampling tool of a wirelineapplication, and a measurement device associated with production tubing,and the like, or combinations thereof.

In an embodiment, a system for making thin film optical elements andmethods of using same as disclosed herein may display advantages whencompared with conventional systems for making thin film optical elementsand methods of using same. Conventionally, thin film optical elementsare fabricated on large substrates which are subsequently cored or sizedinto thin film optical elements of desired sizes. However, fabricating asmall number of customized thin film optical elements entails uniquechallenges, such as difficulty associated with securing substrates withrespect to the deposition plume, individualized quality control etc.

In an embodiment, a system for making thin film optical elements andmethods of using same as disclosed herein can advantageously provide fordepositing substantially uniform thin film stacks on substrates ofdesired shape and size, without the need to further size the obtainedthin film optical elements. Additional advantages of the systems formaking thin film optical elements and methods of using same as disclosedherein may be apparent to one of skill in the art viewing thisdisclosure.

ADDITIONAL DISCLOSURE

A first embodiment, which is a system for making a thin film opticalelement (205) comprising (i) a thin film optical element (205)comprising a substrate (210) and a first thin film stack (230), whereinthe first thin film stack (230) is deposited on a first deposition side(220) of the substrate (210); wherein the first thin film stack (230)comprises two or more film layers; wherein the first thin film stack(230) is characterized by a first uniform film thickness; and whereinthe first uniform film thickness is defined as a thickness variation ofless than about ±5% in any 10 mm² of the first thin film stack (230),when compared to an average first thin film stack thickness across theentire first thin film stack (230), (ii) a holder (100) comprising atleast one holder opening (110); wherein the holder (100) has a holderouter side (102) and a holder inner side (104); wherein the holder outerside (102) has at least one beveled edge (140) extending into a lip(130); wherein the beveled edge (140) and the lip (130) define the atleast one holder opening (110); wherein the lip (130) has asubstantially flat side (131) and a beveled edge side (132); wherein thebeveled edge (140) and/or the beveled edge side (132) of the lip (130)form an angle (135) of less than about 45° with the substantially flatside (131) of the lip (130) and/or the first deposition side (220);wherein the substantially flat side (131) of the lip (130) and theholder inner side (104) define a holder socket (150); wherein the holder(100) is configured to receive the substrate (210) in the holder socket(150); wherein the holder opening (110) is configured to expose thefirst deposition side (220) of the substrate (210) to a deposition plume(250, 433, 435); wherein a portion of the first deposition side (220) ofthe substrate (210) contacts the substantially flat side (131) of thelip (130), thereby allowing for the first thin film stack (230) to bedeposited on the first deposition side (220) of the substrate (210); andwherein the beveled edge side (132) of the lip (130) and/or the bevelededge (140) provide for the first uniform film thickness of the firstthin film stack (230), and (iii) a deposition source configured toprovide the deposition plume (250, 433, 435) for depositing the firstthin film stack (230) on the first deposition side (220) of thesubstrate (210); wherein the deposition plume (250, 433, 435) travelstowards the first deposition side (220) of the substrate (210) at adirection substantially perpendicular to the substantially flat side(131) of the lip (130) and/or to the first deposition side (220) of thesubstrate (210); and wherein the beveled edge side (132) of the lip(130) faces the deposition plume (250, 433, 435).

A second embodiment, which is the system of the first embodiment,wherein a value of the angle (135) between (a) the substantially flatside (131) of the lip (130) and/or the first deposition side (220) ofthe substrate (210), and (b) the beveled edge side (132) of the lip(130) and/or the beveled edge (140) is effective for minimizing edgeeffects of a given deposition plume spatial profile.

A third embodiment, which is the system of any one of the first and thesecond embodiments, wherein the thin film optical element (205) ischaracterized by a size of the first deposition side (220) of thesubstrate (210) of less than about 0.5 inches (12.7 mm).

A fourth embodiment, which is the system of any one of the first throughthe third embodiments, wherein the thin film optical element (205) ischaracterized by a size of the first deposition side (220) of thesubstrate (210) of less than about 0.25 inches (6.4 mm).

A fifth embodiment, which is the system of the third embodiment, whereinthe size of the first deposition side (220) of the substrate (210) isnot modified subsequent to the first thin film stack (230) beingdeposited on the first deposition side (220) of the substrate (210).

A sixth embodiment, which is the system of any one of the first throughthe fifth embodiments, wherein the lip (130) is characterized by aterminal edge (136) that further defines the holder opening (110).

A seventh embodiment, which is the system of the sixth embodiment,wherein the terminal edge (136) is a sharp terminal edge (145).

An eighth embodiment, which is the system of the sixth embodiment,wherein the terminal edge (136) is a blunted terminal edge (240).

A ninth embodiment, which is the system of the sixth embodiment, whereinthe terminal edge (136) is a deflecting terminal edge (440).

A tenth embodiment, which is the system of any one of the first throughthe ninth embodiments, wherein the holder opening (110), the firstdeposition side (220) of the substrate (210), or both the holder opening(110) and the first deposition side (220) of the substrate (210) arecircular (510).

An eleventh embodiment, which is the system of any one of the firstthrough the ninth embodiments, wherein the holder opening (110), thefirst deposition side (220) of the substrate (210), or both the holderopening (110) and the first deposition side (220) of the substrate (210)are elliptical (520).

A twelfth embodiment, which is the system of any one of the firstthrough the ninth embodiments, wherein the holder opening (110), thefirst deposition side (220) of the substrate (210), or both the holderopening (110) and the first deposition side (220) of the substrate (210)are characterized by irregular geometry (530).

A thirteenth embodiment, which is the system of any one of the firstthrough the twelfth embodiments, wherein the substrate (210) has asecond deposition side (225) spatially opposed to the first depositionside (220); wherein the thin film optical element (205) furthercomprises a second thin film stack (231), wherein the second thin filmstack (231) is deposited on the second deposition side (225) of thesubstrate (210); wherein the second thin film stack (231) comprises twoor more film layers; wherein the second thin film stack (231) ischaracterized by a second uniform film thickness; wherein the seconduniform film thickness is defined as a thickness variation of less thanabout ±5% in any 10 mm² of the second thin film stack (231), whencompared to an average second thin film stack thickness across theentire second thin film stack (231).

A fourteenth embodiment, which is the system of the thirteenthembodiment further comprising a mating holder (301); wherein the matingholder (301) contacts the holder (100) and the substrate (210); andwherein the mating holder (301) provides for securing the substrate(210) in place for the deposition of the first thin film stack (230) onthe first deposition side (220) of the substrate (210), the depositionof the second thin film stack (231) on the second deposition side (225)of the substrate (210), or both the deposition of the first thin filmstack (230) on the first deposition side (220) of the substrate (210)and the deposition of the second thin film stack (231) on the seconddeposition side (225) of the substrate (210).

A fifteenth embodiment, which is the system of the fourteenthembodiment, wherein the mating holder (301) comprises at least onemating holder opening (310); wherein the mating holder (301) has amating holder outer side (302) and a mating holder inner side (304);wherein the mating holder inner side (304) contacts the holder innerside (104); wherein the mating holder outer side (302) has at least onebeveled edge (340) extending into a lip (330); wherein the beveled edge(340) and the lip (330) of the mating holder (301) define the at leastone mating holder opening (310); wherein the lip (330) of the matingholder (301) has a substantially flat side (331) and a beveled edge side(332); wherein the beveled edge (340) and/or the beveled edge side (332)of the lip (330) of the mating holder (301) form an angle (335) of lessthan about 45° with the substantially flat side (331) of the lip (330)of the mating holder (301) and/or the second deposition side (225);wherein the substantially flat side (331) of the lip (330) of the matingholder (301) and the mating holder inner side (304) define a matingholder socket (350); wherein the mating holder (301) is configured toreceive the substrate (210) in the mating holder socket (350); whereinthe mating holder opening (310) is configured to expose the seconddeposition side (225) of the substrate (210) to a deposition plume (250,433, 435); wherein a portion of the second deposition side (225) of thesubstrate (210) contacts the substantially flat side (331) of the lip(330) of the mating holder (301), thereby allowing for the second thinfilm stack (231) to be deposited on the second deposition side (225) ofthe substrate (210); wherein the beveled edge side (332) of the lip(330) and/or the beveled edge (340) of the mating holder (301) providefor the second uniform film thickness of the second thin film stack(231); wherein the holder opening (110) and the mating holder opening(310) are the same or different; and wherein the beveled edge side (332)of the lip (330) of the mating holder (301) is the same or different asthe beveled edge side (132) of the lip (130) of the holder (100).

A sixteenth embodiment, which is the system of the fifteenth embodiment,wherein the holder (100) and the mating holder (301) are configured tospatially rotate the secured substrate (210) to provide for thedeposition plume (250, 433, 435) traveling towards the second depositionside (225) of the substrate (210) at a direction substantiallyperpendicular to the substantially flat side (331) of the lip (330) ofthe mating holder (301) and/or to the second deposition side (225) ofthe substrate (210); and wherein the beveled edge side (332) of the lip(330) of the mating holder (301) faces the deposition plume (250, 433,435).

A seventeenth embodiment, which is the system of the sixteenthembodiment, wherein the beveled edge (340) of the mating holder (301)and/or the beveled edge side (332) of the lip (330) of the mating holder(301) are characterized by a geometry effective for minimizing edgeeffects of a given deposition plume spatial profile.

An eighteenth embodiment, which is the system of any one of thethirteenth through the seventeenth embodiments, wherein the thin filmoptical element (205) is characterized by a size of the seconddeposition side (225) of the substrate (210) of less than about 0.5inches (12.7 mm).

A nineteenth embodiment, which is the system of any one of thethirteenth through the eighteenth embodiments, wherein the thin filmoptical element (205) is characterized by a size of the seconddeposition side (225) of the substrate (210) of less than about 0.25inches (6.4 mm).

A twentieth embodiment, which is the system of any one of the thirteenththrough the nineteenth embodiments, wherein the first deposition side(220) and the second deposition side (225) of the substrate (210) aresubstantially parallel to each other.

A twenty-first embodiment, which is the system of any one of thethirteenth through the twentieth embodiments, wherein the firstdeposition side (220) and the second deposition side (225) of thesubstrate (210) are not parallel to each other.

A twenty-second embodiment, which is the system of any one of thethirteenth through the twenty-first embodiments, wherein a distancebetween the first deposition side (220) and the second deposition side(225) of the substrate (210) is less than the size of the firstdeposition side (220) and/or the size of the second deposition side(225).

A twenty-third embodiment, which is the system of any one of thethirteenth through the twenty-first embodiments, wherein a distancebetween the first deposition side (220) and the second deposition side(225) of the substrate (210) is equal to or greater than the size of thefirst deposition side (220) and/or the size of the second depositionside (225).

A twenty-fourth embodiment, which is the system of any one of thethirteenth through the twenty-third embodiments, wherein each of thefirst thin film stack (230) and the second thin film stack (231)independently comprise from about 2 to about 50 layers.

A twenty-fifth embodiment, which is the system of any one of thethirteenth through the twenty-fourth embodiments, wherein each of thefirst thin film stack (230) and the second thin film stack (231)independently comprise from about 7 to about 25 layers.

A twenty-sixth embodiment, which is the system of any one of thethirteenth through the twenty-fifth embodiments, wherein each layer ofthe first thin film stack (230) and/or the second thin film stack (231)is independently characterized by a thickness of from about 0.5 nm toabout 2 μm.

A twenty-seventh embodiment, which is the system of any one of thethirteenth through the twenty-sixth embodiments, wherein each of thefirst thin film stack (230) and/or the second thin film stack (231) isindependently characterized by a thickness of from about 1 nm to about10 jam.

A twenty-eighth embodiment, which is the system of any one of the firstthrough the twenty-seventh embodiments, wherein the substrate (210)comprises an optically transparent material, glass, opticallytransparent glass, silica, sapphire, silicon, germanium, zinc selenide,zinc sulfide, polycarbonate, polymethylmethacrylate (PMMA),polyvinylchloride (PVC), diamond, ceramics, or combinations thereof.

A twenty-ninth embodiment, which is the system of any one of thethirteenth through the twenty-eighth embodiments, wherein each layer ofthe first thin film stack (230) and/or the second thin film stack (231)independently comprises silicon (Si), niobium (Nb), germanium (Ge),binary oxides, quartz, silica (SiO₂), niobia (Nb₂O₅), germania (GeO₂),magnesium fluoride (MgF₂), titania (TiO₂), alumina (Al₂O₃), hafniumdioxide (HfO₂), ternary oxides, or combinations thereof.

A thirtieth embodiment, which is the system of any one of the thirteenththrough the twenty-ninth embodiments, wherein any two adjacent layers ofthe first thin film stack (230) and/or the second thin film stack (231)are characterized by a different refraction index from each other.

A thirty-first embodiment, which is the system of any one of the firstthrough the thirtieth embodiments, wherein the holder (100) comprises aplurality of holder openings (110); wherein the plurality of holderopenings (110) provides for the deposition of a thin film stack on aplurality of substrates (210); and wherein each holder opening (110) isconfigured to allow for the deposition of a thin film stack on anindividual substrate (210).

A thirty-second embodiment, which is a method (2000) for making a thinfilm optical element (205) comprising (a) placing (2100) a substrate(210) in a holder socket (150) of a holder (100); wherein the substrate(210) has a first deposition side (220); wherein the holder (100)comprises at least one holder opening (110); wherein the holder (100)has a holder outer side (102) and a holder inner side (104); wherein theholder outer side (102) has at least one beveled edge (140) extendinginto a lip (130); wherein the beveled edge (140) and the lip (130)define the at least one holder opening (110); wherein the lip (130) hasa substantially flat side (131) and a beveled edge side (132); whereinthe beveled edge (140) and/or the beveled edge side (132) of the lip(130) form an angle (135) of less than about 45° with the substantiallyflat side (131) of the lip (130) and/or the first deposition side (220);wherein the substantially flat side (131) of the lip (130) and theholder inner side (104) define the holder socket (150), and (b)depositing (2200), with a deposition plume (250, 433, 435), a first thinfilm stack (230) on a first deposition side (220) of the substrate (210)to form a thin film optical element (205), wherein the thin film opticalelement (205) comprises the substrate (210) and the first thin filmstack (230) deposited on the first deposition side (220) of thesubstrate (210), wherein the first thin film stack (230) comprises twoor more film layers; wherein the first thin film stack (230) ischaracterized by a first uniform film thickness; and wherein the firstuniform film thickness is defined as a thickness variation of less thanabout ±5% in any 10 mm² of the first thin film stack (230), whencompared to an average first thin film stack thickness across the entirefirst thin film stack (230), wherein a portion of the first depositionside (220) of the substrate (210) contacts the substantially flat side(131) of the lip (130); wherein the holder opening (110) exposes thefirst deposition side (220) of the substrate (210) to the depositionplume (250, 433, 435); wherein the beveled edge side (132) of the lip(130) and/or the beveled edge (140) provide for the first uniform filmthickness of the first thin film stack (230), wherein the depositionplume (250, 433, 435) travels towards the first deposition side (220) ofthe substrate (210) at a direction substantially perpendicular to thesubstantially flat side (131) of the lip (130) and/or to the firstdeposition side (220); and wherein the beveled edge side (132) of thelip (130) faces the deposition plume (250, 433, 435).

A thirty-third embodiment, which is the method (2000) of thethirty-second embodiment further excluding modifying the size of thethin film optical element (205).

A thirty-fourth embodiment, which is the method (2000) of any one of thethirty-second and the thirty-third embodiments, wherein the substrate(210) is sized to a target size prior to depositing the first thin filmstack (230).

A thirty-fifth embodiment, which is the method (2000) of any one of thethirty-second through the thirty-fourth embodiments, wherein adeposition plume spatial profile is tuned in accordance with thegeometry of the beveled edge (140) and/or the geometry of the bevelededge side (132) of the lip (130) to provide for minimizing edge effectsduring depositing the first thin film stack (230).

A thirty-sixth embodiment, which is the method (2000) of thethirty-fifth embodiment, wherein the deposition plume spatial profile istuned by focusing the deposition plume (250, 433, 435); by masking thedeposition plume (250, 433, 435); or both by focusing the depositionplume (250, 433, 435) and by masking the deposition plume (250, 433,435).

A thirty-seventh embodiment, which is the method (2000) of thethirty-sixth embodiment, wherein an electron beam contacts a depositionsource to produce the deposition plume (250, 433, 435), and wherein thedeposition plume spatial profile is tuned by focusing the electron beam,by masking the electron beam, or both by focusing the electron beam andby masking the electron beam.

A thirty-eighth embodiment, which is the method (2000) of thethirty-seventh embodiment, wherein the electron beam is an assisted ionbeam.

A thirty-ninth embodiment, which is the method (2000) of any one of thethirty-second through the thirty-eighth embodiments, wherein thesubstrate (210) has a second deposition side (225) spatially opposed tothe first deposition side (220).

A fortieth embodiment, which is the method (2000) of the thirty-ninthembodiment further comprising inverting (2300) the substrate (210) inthe holder socket (150) subsequent to depositing the first thin filmstack (230); wherein the holder opening (110) exposes the seconddeposition side (225) of the substrate (210) to the deposition plume(250, 433, 435); and wherein a portion of the second deposition side(225) of the substrate (210) contacts the substantially flat side (131)of the lip (130).

A forty-first embodiment, which is the method (2000) of the fortiethembodiment further comprising depositing (2500), with the depositionplume (250, 433, 435), a second thin film stack (231) on the seconddeposition side (225) of the substrate (210); wherein the thin filmoptical element (205) further comprises the second thin film stack (231)deposited on the second deposition side (225) of the substrate (210).

A forty-second embodiment, which is the method (2000) of any one of thethirty-ninth through the forty-first embodiments, wherein a matingholder (301) contacts the holder (100) and the substrate (210), andwherein the mating holder (301) provides for securing the substrate(210) in place for depositing a thin film stack (230, 231) on thesubstrate (210).

A forty-third embodiment, which is the method (2000) of the forty-secondembodiment, wherein the mating holder (301) comprises at least onemating holder opening (310); wherein the mating holder (301) has amating holder outer side (302) and a mating holder inner side (304);wherein the mating holder inner side (304) contacts the holder innerside (104); wherein the mating holder outer side (302) has at least onebeveled edge (340) extending into a lip (330); wherein the beveled edge(340) and the lip (330) of the mating holder (301) define the at leastone mating holder opening (310); wherein the lip (330) of the matingholder (301) has a substantially flat side (331) and a beveled edge side(332); wherein the beveled edge (340) and/or the beveled edge side (332)of the lip (330) of the mating holder (301) form an angle (335) of lessthan about 45° with the substantially flat side (331) of the lip (330)of the mating holder (301) and/or the second deposition side (225);wherein the substantially flat side (331) of the lip (330) of the matingholder (301) and the mating holder inner side (304) define a matingholder socket (350); wherein the mating holder (301) receives thesubstrate (210) in the mating holder socket (350); wherein a portion ofthe second deposition side (225) of the substrate (210) contacts thesubstantially flat side (331) of the lip (330) of the mating holder(301); wherein the holder opening (110) and the mating holder opening(310) are the same or different; and wherein the beveled edge side (332)of the lip (330) of the mating holder (301) is the same or different asthe beveled edge side (132) of the lip (130) of the holder (100).

A forty-fourth embodiment, which is the method (2000) of the forty-thirdembodiment further comprising (i) inverting (2400) the substrate (210)secured in the holder (100) and the mating holder (301) subsequent todepositing the first thin film stack (230); and (ii) depositing (2500),with the deposition plume (250, 433, 435), a second thin film stack(231) on the second deposition side (225) of the substrate (210),wherein the thin film optical element (205) further comprises the secondthin film stack (231) deposited on the second deposition side (225) ofthe substrate (210), wherein the second thin film stack (231) comprisestwo or more film layers; wherein the second thin film stack (231) ischaracterized by a second uniform film thickness; wherein the seconduniform film thickness is defined as a thickness variation of less thanabout +5% in any 10 mm² of the second thin film stack (231), whencompared to an average second thin film stack thickness across theentire second thin film stack (231), wherein the mating holder opening(310) exposes the second deposition side (225) of the substrate (210) tothe deposition plume (250, 433, 435); wherein the beveled edge of thelip of the mating holder opening (310) faces the deposition plume (250,433, 435); and wherein the beveled edge side (332) of the lip (330)and/or the beveled edge (340) of the mating holder (301) provide for thesecond uniform film thickness of the second thin film stack (231).

A forty-fifth embodiment, which is the method (2000) of the forty-fourthembodiment, wherein the thin film optical element (205) is subjected(2600) to quality control analysis, wherein the quality control analysiscomprises at least one analytical technique selected from the groupconsisting of ellipsometry, reflectance spectroscopy, transmissionspectroscopy, and combinations thereof.

A forty-sixth embodiment, which is the method (2000) of the forty-fifthembodiment, wherein the quality control analysis comprises ellipsometryto assess film thickness and uniformity of the first thin film stack(230) and/or the second thin film stack (231).

A forty-seventh embodiment, which is the method (2000) of any one of theforty-fifth and the forty-sixth embodiments, wherein the quality controlanalysis comprises reflectance spectroscopy to assess a reflectancefunction of the thin film optical element (205).

A forty-eighth embodiment, which is the method (2000) of any one of theforty-fifth through the forty-seventh embodiments, wherein the qualitycontrol analysis comprises transmission spectroscopy to assess atransmission function of the thin film optical element (205).

A forty-ninth embodiment, which is the method (2000) of any one of theforty-fifth through the forty-eighth embodiments, wherein the first thinfilm stack (230) is subjected (2600) to quality control analysis priorto and/or subsequent to depositing the second thin film stack (231).

A fiftieth embodiment, which is the method (2000) of any one of theforth-fifth through the forty-ninth embodiments, wherein the first thinfilm stack (230) and/or the second thin film stack (231) are subjected(2600) to quality control analysis.

A fifty-first embodiment, which is the method (2000) of any one of thethirty-second through the fiftieth embodiments, wherein the thin filmoptical element (205) is an integrated computational element (ICE), andwherein the ICE is further employed (2700) in an optical computingdevice.

A fifty-second embodiment, which is the method (2000) of the fifty-firstembodiment, wherein the optical computing device is employed (2700) in adownhole tool in a wellbore penetrating a subterranean formation.

A fifty-third embodiment, which is a holder system for making a thinfilm optical element comprising (i) a holder outer side (102) comprisingat least one beveled edge (140) extending into a lip (130) comprising asubstantially flat side (131) and a beveled edge side (132), wherein thebeveled edge (140) and/or the beveled edge side (132) of the lip (130)form an angle of less than about 45° with the substantially flat side(131) of the lip (130); (ii) at least one holder opening (110) definedby the beveled edge (140) and the lip (130); (iii) a holder inner side(104); and (iv) a holder socket (150) defined by the substantially flatside (131) of the lip (130) and the holder inner side (104), wherein theholder (100) is configured to receive a substrate (210) in the holdersocket (150); and wherein the holder opening (110) is configured toexpose a first deposition side (220) of the substrate (210) to adeposition plume (250, 433, 435).

While embodiments of the invention have been shown and described,modifications thereof can be made by one skilled in the art withoutdeparting from the spirit and teachings of the invention. Theembodiments described herein are exemplary only, and are not intended tobe limiting. Many variations and modifications of the inventiondisclosed herein are possible and are within the scope of the invention.Where numerical ranges or limitations are expressly stated, such expressranges or limitations should be understood to include iterative rangesor limitations of like magnitude falling within the expressly statedranges or limitations (e.g., from about 1 to about 10 includes, 2, 3, 4,etc.; greater than 0.10 includes 0.11, 0.12, 0.13, etc.). For example,whenever a numerical range with a lower limit, R_(L), and an upperlimit, R_(U), is disclosed, any number falling within the range isspecifically disclosed. In particular, the following numbers within therange are specifically disclosed: R=R_(L)+k*(R_(U)−R_(L)), wherein k isa variable ranging from 1 percent to 100 percent with a 1 percentincrement, i.e., k is 1 percent, 2 percent, 3 percent, 4 percent, 5percent, . . . , 50 percent, 51 percent, 52 percent, . . . , 95 percent,96 percent, 97 percent, 98 percent, 99 percent, or 100 percent.Moreover, any numerical range defined by two R numbers as defined in theabove is also specifically disclosed. When a feature is described as“optional,” both embodiments with this feature and embodiments withoutthis feature are disclosed. Similarly, the present disclosurecontemplates embodiments where this feature is required and embodimentswhere this feature is specifically excluded. Both alternatives areintended to be within the scope of the claim. Use of broader terms suchas comprises, includes, having, etc. should be understood to providesupport for narrower terms such as consisting of, consisting essentiallyof, comprised substantially of, etc.

Accordingly, the scope of protection is not limited by the descriptionset out above but is only limited by the claims which follow, that scopeincluding all equivalents of the subject matter of the claims. Each andevery claim is incorporated into the specification as an embodiment ofthe present invention. Thus, the claims are a further description andare an addition to the embodiments of the present invention. Thediscussion of a reference in the Description of Related Art is not anadmission that it is prior art to the present invention, especially anyreference that may have a publication date after the priority date ofthis application. The disclosures of all patents, patent applications,and publications cited herein are hereby incorporated by reference, tothe extent that they provide exemplary, procedural or other detailssupplementary to those set forth herein.

What is claimed is:
 1. A system for making a thin film optical elementcomprising: (i) a thin film optical element comprising a substrate and afirst thin film stack, wherein the first thin film stack is deposited ona first deposition side of the substrate; wherein the first thin filmstack comprises two or more film layers; wherein the first thin filmstack is characterized by a first uniform film thickness; and whereinthe first uniform film thickness is defined as a thickness variation ofless than about ±5% in any 10 mm² of the first thin film stack, whencompared to an average first thin film stack thickness across the entirefirst thin film stack; (ii) a holder comprising at least one holderopening; wherein the holder has a holder outer side and a holder innerside; wherein the holder outer side has at least one beveled edgeextending into a lip; wherein the beveled edge and the lip define the atleast one holder opening; wherein the lip has a substantially flat sideand a beveled edge side; wherein the beveled edge and/or the bevelededge side of the lip form an angle of less than about 45° with thesubstantially flat side of the lip and/or the first deposition side;wherein the substantially flat side of the lip and the holder inner sidedefine a holder socket; wherein the holder is configured to receive thesubstrate in the holder socket; wherein the holder opening is configuredto expose the first deposition side of the substrate to a depositionplume; wherein a portion of the first deposition side of the substratecontacts the substantially flat side of the lip, thereby allowing forthe first thin film stack to be deposited on the first deposition sideof the substrate; and wherein the beveled edge side of the lip and/orthe beveled edge provide for the first uniform film thickness of thefirst thin film stack; and (iii) a deposition source configured toprovide the deposition plume for depositing the first thin film stack onthe first deposition side of the substrate; wherein the deposition plumetravels towards the first deposition side of the substrate at adirection substantially perpendicular to the substantially flat side ofthe lip and/or to the first deposition side of the substrate; andwherein the beveled edge side of the lip faces the deposition plume. 2.The system of claim 1, wherein a value of the angle between (a) thesubstantially flat side of the lip and/or the first deposition side ofthe substrate, and (b) the beveled edge side of the lip and/or thebeveled edge is effective for minimizing edge effects of a givendeposition plume spatial profile.
 3. The system of claim 1, wherein thethin film optical element is characterized by a size of the firstdeposition side of the substrate of less than about 0.5 inches (12.7mm).
 4. The system of claim 1, wherein the lip is characterized by aterminal edge that further defines the holder opening, wherein theterminal edge is selected from the group consisting of a sharp terminaledge, a blunted terminal edge, and a deflecting terminal edge.
 5. Thesystem of claim 1, wherein the substrate has a second deposition sidespatially opposed to the first deposition side; wherein the thin filmoptical element further comprises a second thin film stack, wherein thesecond thin film stack is deposited on the second deposition side of thesubstrate; wherein the second thin film stack comprises two or more filmlayers; wherein the second thin film stack is characterized by a seconduniform film thickness; wherein the second uniform film thickness isdefined as a thickness variation of less than about ±5% in any 10 mm² ofthe second thin film stack, when compared to an average second thin filmstack thickness across the entire second thin film stack.
 6. The systemof claim 5 further comprising a mating holder; wherein the mating holdercontacts the holder and the substrate; wherein the mating holderprovides for securing the substrate in place for the deposition of thefirst thin film stack on the first deposition side of the substrateand/or the deposition of the second thin film stack on the seconddeposition side of the substrate; wherein the mating holder comprises atleast one mating holder opening; wherein the mating holder has a matingholder outer side and a mating holder inner side; wherein the matingholder inner side contacts the holder inner side; wherein the matingholder outer side has at least one beveled edge extending into a lip;wherein the beveled edge and the lip of the mating holder define the atleast one mating holder opening; wherein the lip of the mating holderhas a substantially flat side and a beveled edge side; wherein thebeveled edge and/or the beveled edge side of the lip of the matingholder form an angle of less than about 45° with the substantially flatside of the lip of the mating holder and/or the second deposition side;wherein the substantially flat side of the lip of the mating holder andthe mating holder inner side define a mating holder socket; wherein themating holder is configured to receive the substrate in the matingholder socket; wherein the mating holder opening is configured to exposethe second deposition side of the substrate to a deposition plume;wherein a portion of the second deposition side of the substratecontacts the substantially flat side of the lip of the mating holder,thereby allowing for the second thin film stack to be deposited on thesecond deposition side of the substrate; wherein the beveled edge sideof the lip and/or the beveled edge of the mating holder provide for thesecond uniform film thickness of the second thin film stack; wherein theholder opening and the mating holder opening are the same or different;and wherein the beveled edge side of the lip of the mating holder is thesame or different as the beveled edge side of the lip of the holder. 7.The system of claim 6, wherein the holder and the mating holder areconfigured to spatially rotate the secured substrate to provide for thedeposition plume traveling towards the second deposition side of thesubstrate at a direction substantially perpendicular to thesubstantially flat side of the lip of the mating holder and/or to thesecond deposition side of the substrate; wherein the beveled edge sideof the lip of the mating holder faces the deposition plume; and whereinthe beveled edge of the mating holder and/or the beveled edge side ofthe lip of the mating holder are characterized by a geometry effectivefor minimizing edge effects of a given deposition plume spatial profile.8. The system of claim 5, wherein each of the first thin film stack andthe second thin film stack independently comprise from about 2 to about50 layers; wherein each layer of the first thin film stack and/or thesecond thin film stack is independently characterized by a thickness offrom about 0.5 nm to about 2 μm; wherein each of the first thin filmstack and/or the second thin film stack is independently characterizedby a thickness of from about 1 nm to about 10 μm; and wherein any twoadjacent layers of the first thin film stack and/or the second thin filmstack are characterized by a different refraction index from each other.9. The system of claim 5, wherein the substrate comprises an opticallytransparent material, glass, optically transparent glass, silica,sapphire, silicon, germanium, zinc selenide, zinc sulfide,polycarbonate, polymethylmethacrylate (PMMA), polyvinylchloride (PVC),diamond, ceramics, or combinations thereof; and wherein each layer ofthe first thin film stack and/or the second thin film stackindependently comprises silicon (Si), niobium (Nb), germanium (Ge),binary oxides, quartz, silica (SiO₂), niobia (Nb₂O₅), germania (GeO₂),magnesium fluoride (MgF₂), titania (TiO₂), alumina (Al₂O₃), hafniumdioxide (HfO₂), ternary oxides, or combinations thereof.
 10. The systemof claim 1, wherein the holder comprises a plurality of holder openings;wherein the plurality of holder openings provides for the deposition ofa thin film stack on a plurality of substrates; and wherein each holderopening is configured to allow for the deposition of a thin film stackon an individual substrate.
 11. A method for making a thin film opticalelement comprising: (a) placing a substrate in a holder socket of aholder; wherein the substrate has a first deposition side; wherein theholder comprises at least one holder opening; wherein the holder has aholder outer side and a holder inner side; wherein the holder outer sidehas at least one beveled edge extending into a lip; wherein the bevelededge and the lip define the at least one holder opening; wherein the liphas a substantially flat side and a beveled edge side; wherein thebeveled edge and/or the beveled edge side of the lip form an angle ofless than about 45° with the substantially flat side of the lip and/orthe first deposition side; wherein the substantially flat side of thelip and the holder inner side define the holder socket; and (b)depositing, with a deposition plume, a first thin film stack on a firstdeposition side of the substrate to form a thin film optical element,wherein the thin film optical element comprises the substrate and thefirst thin film stack deposited on the first deposition side of thesubstrate; wherein the first thin film stack comprises two or more filmlayers; wherein the first thin film stack is characterized by a firstuniform film thickness; and wherein the first uniform film thickness isdefined as a thickness variation of less than about ±5% in any 10 mm² ofthe first thin film stack, when compared to an average first thin filmstack thickness across the entire first thin film stack; wherein aportion of the first deposition side of the substrate contacts thesubstantially flat side of the lip; wherein the holder opening exposesthe first deposition side of the substrate to the deposition plume;wherein the beveled edge side of the lip and/or the beveled edge providefor the first uniform film thickness of the first thin film stack;wherein the deposition plume travels towards the first deposition sideof the substrate at a direction substantially perpendicular to thesubstantially flat side of the lip and/or to the first deposition side;and wherein the beveled edge side of the lip faces the deposition plume.12. The method of claim 11 further excluding modifying the size of thethin film optical element; wherein the substrate is sized to a targetsize prior to depositing the first thin film stack.
 13. The method ofclaim 11, wherein a deposition plume spatial profile is tuned inaccordance with the geometry of the beveled edge and/or the geometry ofthe beveled edge side of the lip to provide for minimizing edge effectsduring depositing the first thin film stack.
 14. The method of claim 13,wherein the deposition plume spatial profile is tuned by focusing thedeposition plume; by masking the deposition plume; or both by focusingthe deposition plume and by masking the deposition plume.
 15. The methodof claim 11, wherein the substrate has a second deposition sidespatially opposed to the first deposition side.
 16. The method of claim15 further comprising (A) inverting the substrate in the holder socketsubsequent to depositing the first thin film stack; wherein the holderopening exposes the second deposition side of the substrate to thedeposition plume; and wherein a portion of the second deposition side ofthe substrate contacts the substantially flat side of the lip; and (B)depositing, with the deposition plume, a second thin film stack on thesecond deposition side of the substrate; wherein the thin film opticalelement further comprises the second thin film stack deposited on thesecond deposition side of the substrate.
 17. The method of claim 15,wherein a mating holder contacts the holder and the substrate; whereinthe mating holder provides for securing the substrate in place fordepositing a thin film stack on the substrate; wherein the mating holdercomprises at least one mating holder opening; wherein the mating holderhas a mating holder outer side and a mating holder inner side; whereinthe mating holder inner side contacts the holder inner side; wherein themating holder outer side has at least one beveled edge extending into alip; wherein the beveled edge and the lip of the mating holder definethe at least one mating holder opening; wherein the lip of the matingholder has a substantially flat side and a beveled edge side; whereinthe beveled edge and/or the beveled edge side of the lip of the matingholder form an angle of less than about 45° with the substantially flatside of the lip of the mating holder and/or the second deposition side;wherein the substantially flat side of the lip of the mating holder andthe mating holder inner side define a mating holder socket; wherein themating holder receives the substrate in the mating holder socket;wherein a portion of the second deposition side of the substratecontacts the substantially flat side of the lip of the mating holder;wherein the holder opening and the mating holder opening are the same ordifferent; and wherein the beveled edge side of the lip of the matingholder is the same or different as the beveled edge side of the lip ofthe holder.
 18. The method of claim 17 further comprising (i) invertingthe substrate secured in the holder and the mating holder subsequent todepositing the first thin film stack; and (ii) depositing, with thedeposition plume, a second thin film stack on the second deposition sideof the substrate, wherein the thin film optical element furthercomprises the second thin film stack deposited on the second depositionside of the substrate; wherein the second thin film stack comprises twoor more film layers; wherein the second thin film stack is characterizedby a second uniform film thickness; wherein the second uniform filmthickness is defined as a thickness variation of less than about +5% inany 10 mm² of the second thin film stack, when compared to an averagesecond thin film stack thickness across the entire second thin filmstack; wherein the mating holder opening exposes the second depositionside of the substrate to the deposition plume; wherein the beveled edgeof the lip of the mating holder opening faces the deposition plume; andwherein the beveled edge side of the lip and/or the beveled edge of themating holder provide for the second uniform film thickness of thesecond thin film stack.
 19. The method of claim 18, wherein the thinfilm optical element is subjected to quality control analysis, whereinthe quality control analysis comprises at least one analytical techniqueselected from the group consisting of ellipsometry, reflectancespectroscopy, transmission spectroscopy, and combinations thereof. 20.The method of claim 11, wherein the thin film optical element is anintegrated computational element (ICE); wherein the ICE is employed inan optical computing device; and wherein the optical computing device isfurther employed in a downhole tool in a wellbore penetrating asubterranean formation.
 21. A holder system for making a thin filmoptical element comprising: a holder outer side comprising at least onebeveled edge extending into a lip comprising a substantially flat sideand a beveled edge side, wherein the beveled edge and/or the bevelededge side of the lip form an angle of less than about 45° with thesubstantially flat side of the lip; at least one holder opening definedby the beveled edge and the lip; a holder inner side; and a holdersocket defined by the substantially flat side of the lip and the holderinner side, wherein the holder is configured to receive a substrate inthe holder socket, and wherein the holder opening is configured toexpose a first deposition side of the substrate to a deposition plume.